Devices for detecting broken ends or strands on textile machinery



Nov. 12, 1957 J. TILLETT, JR 2,812,632

DEVICES FOR DETECTING BROKEN ENDS 0R STRANDS 1 ON TEXTILE MACHINERY Filed March 10, 1953 2 Sheets-Sheet 1 INVENTOR.

Nov. 12, 1957 J. TILLETT, JR 2,812,632

DEVICES FOR DETECTING BROKEN ENDS OR STRANDS 7 ON TEXTILE MACHINERY Filed March 10, 1953 2 Sheets-Sheet 2 v F IG. 3

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l4 l- I 30 LI 1\ l3 T T 1 A l '-2 L2 I1 INVENTOR. M 7166222? EVECES 1 6R DETECTING BROKEN ENDS OR STRANDS N TEXTILE MACHINERY John Tillett, n, Charlotte, N. C., assignor to Pnenmafil Corporation, Charlotte, N. C., a corporation of Delaware Application March 10, 1953, Serial No. 341,548

12 Claims. (Cl. 57-34.5)

This invention relates to a device for detecting broken ends on textile machinery and, more particularly, to a device for the actuation of suitable mechanism to discontinue operation of the frame upon the occurrence of a broken end and/ or to warn the operator of the frame of the broken end. Any strand of textile material such as a sliver, roving, yarn, thread, cord, etc. is referred to herein as an end.

The chief object of the present invention is to provide a device for detecting broken ends on a textile frame which is capable of discontinuing operation of the frame and/or warning the operator of the frame of the occurrence of such broken end.

An object is to provide a device for detecting broken ends on a textile frame in which suction means are employed to draw a broken end past electrical means responsive to the broken end to actuate indicating means and/ or to discontinue operation of the frame.

A further object is to provide a device inwhich a broken end is drawn through an air gap capacitor by means of an exhaust or suction device, entrance of the end into the capacitor gap energizing the device to shut down the frame or to indicate to the frame operator the occurrence of the broken end or both.

A still further object is to provide a detecting device including a plurality of air gap capacitor inductance units and a potentiometer in which a broken end is drawn into the air gap of the capacitor of any of the units by means of an exhaust or suction device, entry of the broken end into the air gap changing the interrelationship between the voltages across the units and the potentiometer in such manner that a relay circuit is closed to shut down the frame and/ or to warn the operator of the occurrence of the broken end. Other objects of my invention will be readily perceived from the following description.

This invention relates to a device for detecting broken ends or strands on a textile frame having a plurality of rolls to draw the ends comprising, in combination, means to receive a broken end from the rolls of the frame, a storage compartment for broken ends, a duct to carry broken ends from said means to the storage compartment, suction means for drawing a broken end in said first means and through the duct, electrical means responsive to passage of a broken end into the duct, and means responsive to the electrical means to indicate the broken end to the operator and/ or to discontinue operation of the frame.

This invention further relates to a device for detecting broken ends on a textile frame and comprises, in combination, an air gap capacitor-inductance unit having the capacitor and inductance connected in series with the inductance tuned olf resonance with the capacitor, exhaust means for drawing the broken end through the air gap of the capacitor, introduction of the broken end into the air gap of the capacitor bringing the unit substantially into resonance, a resistance in series with the unit, total voltage drop across the unit and the resistance being substantially constant, resonance of the unit diminishing the voltage drop across the unit and increasing the voltage 3 States Patent 0 2 drop across the resistance, and means for utilizing the change in voltage to actuate indicating means.

The attached drawings illustrate a preferred embodiment of my invention, in which Figure 1 is a front elevation view of a portion of a textile frame provided with the present. invention;

Figure 2 is a view taken on the line II-II of Figure 1;

Figure 3 is a diagrammatic view of the electrical circuit of the detecting device; and

Figure 4 is a view similar to Figure 3 of a modification of the invention.

Referring to the drawings, there is shown in Figures 1 and 2 a portion of a textile frame including sets of rolls 2 and 3 through which ends 4 are drawn to straighten and apply the final draft to the fibers composing the end.

A hollow tube 5 extends longitudinally of the frame below the various sets of rolls 2, 3 and is provided with slots 6 through which a broken end 7 is drawn into tube 5. Tube 5 is connected by tubes 8 with a suitable suction or exhaust device such as a fan F which draws the broken end into tube 5, and through tube 8 into the storage compartment or container 9.

A detecting device indicated generally at 10 is provided including units 11 preferably placed in tubes or ducts 8, each unit including an air gap capacitor 13 and an inductance 14, the broken end 7 being drawn through the air gap 12 of capacitor 13. The unit 11 may be placed, if desired, at other suitable locations, for example, a unit 11 may be placed in the collecting duct or header to function as a device to indicate broken ends. The capacitor 13 and its accompanying inductance 14 are tuned out of resonance. Introduction of the broken end 7 into the air gap 12 brings the capacitor 13 and inductance 14 substantially into resonance thus diminishing the voltage drop across the unit 11.

The detecting device 10 includes a suitable radio frequencygenerator and amplifier 15 connected by connector 16 to a plurality of air gap capacitor-inductance units 11 disposed in parallel, each unit preferably being arranged to detect a broken end 7 from each set of rolls 2, 3. A potentiometer 17 is placed in series with units 11 by connector 18, the potentiometer 17 being connected to generator and amplifier 15 by connector 19.

The indicating means include a diode tube 20 connected to connector 18 by connector 21. The diode tube 20 conducts in one direction only. A connector 22 connects the cathode 23 of diode 20 to connector 19, a capacitor 24 being placed in connector 22. 'A connector 25 connects the grid 26 of a glow discharge triode tube 27 with connector 22 at .a point between capacitor 24 and cathode 23. A resistor 28 is connected between connectors 25 and 22 about capacitor 24. The cathode 29 of triode 27 is connected to a relay 30, connected to the motor 31 of the frame and also to a signal lamp 32. It will be understood, of course, the relay may be connected to the motor, to the lamp or to both as desired. Thus, to indicate a broken end 7 which has entered the air gap 12 of a unit 11, the voltage rise across the potentiometer 17 is measured.

Considering the operation of the detecting device, a broken end 7 is drawn by the vacuum means F into the air gap 12 (between the plates) of capacitor 13 connected in series with variable inductance 14 which is tuned off resonance with the capacitor. When the broken end is introduced between the plates of this capacitor, the capacitance of the capacitor 13 is changed bringing the A-B series connection to or near resonance. At or near resonance, the reactance of this series connection dips sharply. Thus, the voltage across this A-B connection decreases proportionately, most of the voltage drop in the circuit now appearing across the potentiometer '17, the resistance of the potentiometer 17 being large with respect to the reactance of the AB connection at or near resonance. The same thing happens even though there are a plurality of units 11 connected in parallel although only one such unit is caused to resonate by the introduction 'of a broken end between the plates of its capacitor.

The voltage rise across potentiometer 17 is measured. Diode 20 will conduct in one direction only. As the diode conducts during the half cycle when the plate is positive with respect to cathode 23, a positive charge builds up in the cathode side of capacitor 24. This charge can draw off only through resistor 28, the resistance of which is very high. The time required for the charge to be drawn off is long with respect to the frequency of charging of condenser 24. Therefore, a charge builds up and remains on the cathode side of capacitor 24 equal to the peak voltage across potentiometer 17 and the diode 20 ceases to conduct since the voltage drop from cathode to anode is not enough to cause conduction. The cathode 23 of diode 20 is directly connected to the grid 26 of triode 27.

As an increase in voltage appears across the potentiometer, diode 2t} conducts until this new peak charge is placed on capacitor 24 to cause diode 20 to cease conducting. As the potential of the cathode 23 of diode 20 increases so does the grid potential of triode 27. When such grid potential reaches a predetermined point the gaseous triode begins to conduct closing the relay 30. Relay 30 opens the circuit of the frame motor 31, stopping operation of the frame, and closing the circuit to light warning lamp 32 to signal that an end has broken.

It will be appreciated that the electrical arrangement of units 11 is such that if any unit is caused to resonate or approach resonance then a voltage drop occurs across the entire electrical circuit between point A and point B. The interrelationship between the voltages across points AB and potentiometer 17 is employed in such manner that a rise in voltage across potentiometer 17 causes the relay circuit to be closed. While the total voltage drop across points AB plus potentiometer 17 remains constant, it will be appreciated as any one of units 11 approaches resonance, the voltage drop across points AB diminishes rapidly and the voltage drop across potentiometer 17 increases.

In Figure 4, I have shown a modification of the invention in which the voltage drop across points AB is measured to detect the changes in voltage across points AB and potentiometer 17. In this case, a voltmeter 35 is employed to measure the voltage drop across points A-B. Upon introduction of a broken end into the air gap 12 of a capacitor 13, the voltage across points AB drops below a predetermined limit since the capacitor 13 and inductance 14 of the unit 11 is at or near resonance; the Swinging arm of voltmeter 35 contacts a terminal closing the relay circuit to stop the frame motor or to actuate a warning lamp or to do both as desired.

The present invention provides an inexpensive and simple device to detect broken ends in a textile frame and to stop the frame or to warn the operator of the broken end as desired. The device functions by the introduction of the broken end between the plates of an air gap capacitor by the suction system thus bringing the capacitor and its accompanying inductance into or near resonance to actuate the signalling or indicating mechanism. The device may be easily and simply applied to any desired number of rolls of the frame without extensive revision of the machine.

While I have described a preferred embodiment of my invention, it will be understood my invention is not limited thereto since it may be otherwise embodied within the scope of the following claims.

I claim:

'1. 'in a device for detecting broken ends in a textile frame, the combination of an air gap capacitor-inductance unit having the capacitor and inductance connected in series with the inductance tuned oif resonance with the capacitor, exhaust means for drawing the broken end through the air gap of the capacitor, introduction of the broken end into the air gap of the capacitor bringing the unit substantially into resonance, a resistance in series with the unit, total voltage drop across the unit and the resistance being substantially constant, resonance of the unit diminishing the voltage drop across the unit and increasing the voltage drop across the resistance, and means for utilizing the change in voltage to actuate indicating means.

2. A device according to claim 1 in which means are provided to warn of the broken end.

3. in a device for detecting broken ends in a textile frame, the combination of an air gap capacitor-inductance unit having the capacitor and inductance connected in series with the inductance tuned off resonance with the capacitor, exhaust means for drawing the broken end through the air gap of the capacitor, introduction of the broken end into the air gap of the capacitor bringing the unit substantially into resonance, a resistance in series with the unit, total voltage drop across the unit and the resistance being substantially constant, resonance of the unit diminishing the voltage drop across the unit and increasing the voltage drop across the resistance, a relay, the change in voltage closing the relay circuit, and indicating means actuated by the relay.

4. A device according to claim 1 in which a plurality of units are provided connected in parallel in the circuit.

5. In a device for indicating broken ends in a textile frame, the combination of an air gap capacitor-inductance unit having the capacitor and inductance connected in series with the inductance tuned olf resonance with the capacitor, exhaust means for drawing the broken end into the air gap of the capacitor, introduction of the broken end into the air gap of the capacitor bringing the unit substantially into resonance, a potentiometer in series with the unit, total voltage drop across the unit and the potentiometer being substantially constant, resonance of the unit diminishing the voltage drop across the unit and increasing the voltage drop across the potentiometer, and means for utilizing the change in voltage to actuate indicating means.

6. A device according to claim 5 in which the actuating means include a diode tube, a glow discharge triode tube, a resistance, a second capacitor, a relay and indica means, the whole being so arranged and constructed tha upon an increase in voltage across the potentiometer the diode tube conducts until such charge is placed on the second capacitor so that as the potential of the cathode of the diode increases the grid potential of the gaseous triode increases to a predetermined point whereupon the triode begins to conduct closing the relay circuit to actuate the indicating means.

7. In a detecting device, the combination of an electrical circuit, a plurality of air gap capacitor-inductance units connected in parallel in the circuit, the capacitor and inductance of each unit being connected in series in the circuit, means for passing the matter to be detected through the air gap of a capacitor, introduction of matter into the air gap bringing that unit substantially into resonance, a potentiometer in series with the units, total voltage drop across the units and the potentiometer being substantially constant, introduction of the matter to be detected into the air gap of the capacitor of any unit bringing the capacitor and inductance of that unit into substantial resonance, resonance of the unit diminish ing the voltage drop across the units and increasing th voltage drop across the potentiometer, indicating means, and means for utilizing the change in voltage to actuate the indicating means.

8. A device according to claim 7 in which the actuating means include a relay, the change in voltage closing the relay circuit to actuate the indicating means.

9. A device according to claim 8 in which a predetermined rise in voltage across the potentiometer closes the relay circuit.

10. A device according to claim 9 in which the actuating means include a diode tube, a glow discharge triode tube, a resistance, a second capacitor and indicating means, the whole being so constructed and arranged that upon an increase in voltage across the potentiometer the diode tube conducts until such charge is placed on the second capacitor, so that as the potential of the cathode of the diode tube increases the grid potential of the gaseous triode tube increases to a predetermined point whereupon the triode begins to conduct closing the relay circuit to actuate the indicating means.

11. In combination with a textile frame having a plurality of rolls to draw textile ends, a motor to actuate the rolls, and means for removing broken ends from the rolls, a detecting device for indicating breakage of any strand, said device comprising an electrical circuit including a plurality of air gap capacitor-inductance units disposed in parallel with the capacitor and inductance of each unit arranged in series, the inductance of each unit being tuned off resonance with the capacitor, introduction of an end into the air gap of a capacitor of any unit bringing the unit substantially into resonance, a potentiometer in series in the circuit with the units, total voltage drop across the units and the potentiometer being substantially constant, resonance of any unit diminishing the voltage drop across the unit and increasing the voltage drop across the potentiometer, and means for utilizing the change in voltage to actuate indicating means.

12. A device according to claim 11 in which a relay is provided, the change in voltage closing the relay circulit, and indicating means actuated by the relay.

References Cited in the file of this patent UNITED STATES PATENTS 2,390,799 Linsenmeyer et al. Dec. 11, 1945 2,438,365 Hepp et a1 Mar. 23, 1948 2,500,343 Carrette Mar. 14, 1950 2,522,250 Bechtler Sept. 12, 1950 2,531,944 Metcalf Nov. 28, 1950 2,671,199 Truitt Mar. 2, 1954 FOREIGN PATENTS 506,610 Belgium Nov. 14, 1951 

